Predictors of Sinonasal Improvement After Highly Effective Modulator Therapy in Adults with Cystic Fibrosis.

OBJECTIVES: The 22-question SinoNasal Outcome Test (SNOT-22) assesses chronic rhinosinusitis (CRS) severity. We aimed to identify predictors of SNOT-22 score improvement following highly effective modulator therapy (HEMT) initiation and to corroborate the SNOT-22 minimal clinically important difference (MCID) in adults with cystic fibrosis (CF). METHODS: Prospective observational data was pooled from four studies across 10 US centers investigating people with CF (PwCF) and CRS. Three studies evaluated HEMT's impact on CRS. For participants enrolled prior to HEMT initiation, SNOT-22 scores were obtained at baseline and after 3-6 months of HEMT. Multivariate regression identified predictors of improvement. Cronbach's alpha and four distribution-based methods were used to assess internal consistency and calculate the MCID of the SNOT-22. RESULTS: A total of 184 PwCF participated with mean baseline SNOT-22 scores ranging from 18.1 to 56.7. Cronbach's alpha was ≥0.90 across sites. Participants at sites with pre- and post-HEMT data reported improvement in SNOT-22 scores after initiating HEMT (all p < 0.05). Worse baseline SNOT-22 score (odds ratio (OR): 1.05, p < 0.001, 95% CI: 1.02-1.08), F508del homozygosity (OR: 4.30, p = 0.040, 95% CI: 1.14-18.99), and absence of prior modulator therapy (OR: 4.99, p = 0.017, 95% CI: 1.39-20.11) were associated with greater SNOT-22 improvement. The mean MCID calculated via distribution-based methods was 8.5. CONCLUSION: Worse baseline sinonasal symptoms, F508del homozygosity, and absence of prior modulator therapy predicted greater improvement after HEMT initiation. The mean MCID for SNOT-22 in PwCF is 8.5 points, similar to non-CF individuals with CRS, and provides a threshold specifically for PwCF. The SNOT-22 has strong internal consistency in PwCF. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

Association between CFTR modulators and changes in iron deficiency markers in cystic fibrosis.

BACKGROUND: Iron deficiency (ID) is a common extrapulmonary manifestation in cystic fibrosis (CF). CF transmembrane conductance regulator (CFTR) modulator therapies, particularly highly-effective modulator therapy (HEMT), have drastically improved health status in a majority of people with CF. We hypothesize that CFTR modulator use is associated with improved markers of ID. METHODS: In a multicenter retrospective cohort study across 4 United States CF centers 2012-2022, the association between modulator therapies and ID laboratory outcomes was estimated using multivariable linear mixed effects models overall and by key subgroups. Summary statistics describe the prevalence and trends of ID, defined a priori as transferrin saturation (TSAT) <20 % or serum iron <60 µg/dL (<10.7 µmol/L). RESULTS: A total of 568 patients with 2571 person-years of follow-up were included in analyses. Compared to off modulator therapy, HEMT was associated with +8.4 % TSAT (95 % confidence interval [CI], +6.3-10.6 %; p < 0.0001) and +34.4 µg/dL serum iron (95 % CI, +26.7-42.1 µg/dL; p < 0.0001) overall; +5.4 % TSAT (95 % CI, +2.8-8.0 %; p = 0.0001) and +22.1 µg/dL serum iron (95 % CI, +13.5-30.8 µg/dL; p < 0.0001) in females; and +11.4 % TSAT (95 % CI, +7.9-14.8 %; p < 0.0001) and +46.0 µg/dL serum iron (95 % CI, +33.3-58.8 µg/dL; p < 0.0001) in males. Ferritin was not different in those taking modulator therapy relative to off modulator therapy. Hemoglobin was overall higher with use of modulator therapy. The prevalence of ID was high throughout the study period (32.8 % in those treated with HEMT). CONCLUSIONS: ID remains a prevalent comorbidity in CF, despite availability of HEMT. Modulator use, particularly of HEMT, is associated with improved markers for ID (TSAT, serum iron) and anemia (hemoglobin).

Prioritizing sexual and reproductive health research and care for people with cystic fibrosis: A 2023 workshop report from the Cystic Fibrosis Foundation Sexual Health, Reproduction, and Gender (SHARING) Research Working Group.

BACKGROUND: To address sexual and reproductive health (SRH) concerns among people with cystic fibrosis(PwCF), the CF Foundation created the Sexual Health, Reproduction, and Gender Research (SHARING) Working Group. This report summarizes CF community SRH research priorities and workshop discussions/future study planning. METHODS: Pre-workshop, we distributed a community prioritization survey on CF SRH research/care. During the workshop, we used results and reviewed existing research to establish research priorities and design studies to address identified knowledge gaps. RESULTS: A total of 303 respondents (85 % PwCF, 15 % caregivers) completed the survey. Highly-rated SRH topics were: 1) effects of CF modulator therapy on sex hormones; 2) effects of sex hormones on CF; 3) fertility; 4) pregnancy; and 5) SRH/mental health. Twenty-four workshop participants established the need for further research on sex hormones and CF, optimizing SRH care provision, and fertility/ART. CONCLUSION: SRH is an important and emerging area in CF and thoughtful consideration of community perspectives can ensure that future research is relevant and responsive.

Patient perspectives on chronic rhinosinusitis in cystic fibrosis: Symptom prioritization in the era of highly effective modulator therapy.

BACKGROUND: Chronic rhinosinusitis (CRS) is common in people with cystic fibrosis (PwCF). Rhinologic symptom prioritization and areas that influence CRS treatment choices, including pursuing endoscopic sinus surgery (ESS), remain understudied. METHODS: Adult PwCF + CRS were enrolled at eight centers into a prospective, observational study (2019-2023). Participants were administered the 22-SinoNasal Outcome Test (SNOT-22) survey and a modified SNOT-22 instrument examining symptom importance. We determined importance rankings for individual symptoms and SNOT-22 symptom importance subdomains in two sets of subgroups-those pursuing ESS versus continuing medical management (CMT), and those on elexacaftor/tezacaftor/ivacaftor (ETI) versus not on ETI. RESULTS: Among 69 participants, the highest priorities were nasal congestion (n = 48, 69.6% important), post-nasal discharge (32, 46.4%), facial pain (29, 43.3%), waking up tired (27, 39.1%), and fatigue (26, 37.7%). Those electing surgery (n = 23) prioritized sleep and psychological dysfunction symptoms compared to those pursuing CMT (n = 49) (sleep median score = 19.0 [interquartile range: 12.0, 25.0] vs. 4.5 [0.0, 12.8]; p < 0.0001; psychological = 17.0 [7.0, 26.0] vs. 7.0 [0.0, 15.8]; p = 0.002). ETI users had comparable SNOT-22 total symptom importance scores to non-ETI users (p = 0.14). Non-ETI users (n = 34) showed a trend toward prioritizing sleep symptoms compared to ETI users (n = 35) (13.0 [2.8, 22.3] vs. 6.0 [2.0, 17.0]; p = 0.055). CONCLUSIONS: Nasal congestion and post-nasal discharge were top priorities reported by PwCF + CRS. Those electing surgery prioritized sleep and psychological symptoms, highlighting their importance in pre-operative discussions. Non-ETI users' prioritization of sleep improvement may highlight their unique disease impact and therapeutic needs; however, additional investigation is required.

Airway inflammation accelerates pulmonary exacerbations in cystic fibrosis.

Airway inflammation underlies cystic fibrosis (CF) pulmonary exacerbations. In a prospective multicenter study of randomly selected, clinically stable adolescents and adults, we assessed relationships between 24 inflammation-associated molecules and the future occurrence of CF pulmonary exacerbation using proportional hazards models. We explored relationships for potential confounding or mediation by clinical factors and assessed sensitivities to treatments including CF transmembrane regulator (CFTR) protein synthesis modulators. Results from 114 participants, including seven on ivacaftor or lumacaftor-ivacaftor, representative of the US CF population during the study period, identified 10 biomarkers associated with future exacerbations mediated by percent predicted forced expiratory volume in 1 s. The findings were not sensitive to anti-inflammatory, antibiotic, and CFTR modulator treatments. The analyses suggest that combination treatments addressing RAGE-axis inflammation, protease-mediated injury, and oxidative stress might prevent pulmonary exacerbations. Our work may apply to other airway inflammatory diseases such as bronchiectasis and the acute respiratory distress syndrome.

Factors that predict pursuing sinus surgery in the era of highly effective modulator therapy.

BACKGROUND: Comorbid chronic rhinosinusitis (CRS) remains unresolved for many people with cystic fibrosis (PwCF). While highly effective modulator therapy improves quality-of-life and symptom severity, the impact of this intervention and other factors associated with pursuing endoscopic sinus surgery (ESS) remains understudied. METHODS: Adult PwCF + CRS were enrolled into a prospective, observational, multi-institutional study. Participants completed validated outcome measures to evaluate respiratory symptom severity, depression, headache, and sleep quality, as well as nasal endoscopy, sinus computed tomography (CT), and olfactory testing. Bivariate comparisons and regression modeling evaluated treatment cofactors, disease characteristics, and outcome measures associated with pursuing ESS. RESULTS: Sixty PwCF were analyzed, including 24 (40%) who elected ESS. Pursuing ESS was associated with worse SinoNasal Outcome Test (SNOT-22) total, rhinologic, psychological, and sleep dysfunction domain scores; worse Patient Health Questionnaire-9-Revised depression scores; worse Pittsburgh Sleep Quality Index total scores; worse weight, role, emotion, and eating domain scores on the Cystic Fibrosis Questionnaire-Revised; more severe disease on nasal endoscopy; and lack of modulator therapy (all p < 0.050). Multivariable regression identified that worse SNOT-22 total score was associated with electing ESS (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.02-1.16, p = 0.015) and elexacaftor/tezacaftor/ivacaftor (ETI) treatment (OR 0.04, 95% CI 0.004-0.34, p = 0.004) was associated with pursing medical therapy. CONCLUSIONS: Worse sinonasal symptom burden, lack of ETI treatment, sleep quality, depression, and nasal endoscopy scores were associated with electing ESS, while lung disease severity and sinus CT scores were not. ETI use was associated with lower odds of pursuing ESS independent of sinonasal symptom burden.

Elexacaftor/Tezacaftor/Ivacaftor Treatment and Depression-related Events.

Rationale: Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) has been shown to be safe and efficacious in people with cystic fibrosis (pwCF) aged 2 years and older with at least one F508del-CFTR allele or more. After U.S. approval in 2019, reports emerged of depression-related adverse events in pwCF treated with ELX/TEZ/IVA. Objectives: To review available evidence on depression-related events in pwCF treated with ELX/TEZ/IVA in the context of background epidemiology in pwCF. Methods: Safety data from 14 ELX/TEZ/IVA clinical trials and 10 trials of CF transmembrane conductance regulator (CFTR) modulators in which placebo was administered, along with data from CF registries in the United States and Germany and cumulative postmarketing adverse event data from 61,499 pwCF who initiated ELX/TEZ/IVA after initial approval in the United States (October 2019) through October 2022, were reviewed and used to calculate exposure-adjusted rates of depression-related adverse events and prevalence of depression. In addition, a scientific literature review was conducted to identify ELX/TEZ/IVA publications reporting depression-related events or changes in depressive symptoms after treatment initiation. Measurements and Main Results: In clinical trials, the exposure-adjusted rate of any depression-related adverse event was 3.32/100 person years (PY) in the pooled ELX/TEZ/IVA group (n = 1,711) and 3.24/100 PY in the pooled placebo group (n = 1,369). The exposure-adjusted rates of suicidal ideation and suicide attempt were also similar between the pooled ELX/TEZ/IVA group and pooled placebo group (ideation: 0.23/100 PY vs. 0.28/100 PY; attempt: 0.08/100 PY vs. 0.14/100 PY). In the postmarketing setting, the exposure-adjusted reporting rates of depression-related events were low in context of the background prevalence in pwCF (all depression-related events: 1.29/PY; suicidal ideation: 0.12/100 PY; and suicide attempt: 0.05/100 PY). Assessments of individual case reports were confounded by preexisting mental health conditions, intercurrent psychosocial stressors (including coronavirus disease [COVID-19] lockdowns), and the heterogeneous and fluctuating nature of depression. Data from CF registries in the United States and Germany showed that patterns of depression prevalence in pwCF exposed to ELX/TEZ/IVA did not change after treatment initiation. Published studies utilizing the nine-item Patient Health Questionnaire did not show evidence of worsening depression symptoms in pwCF treated with ELX/TEZ/IVA. Conclusions: Our review of data from clinical trials, postmarketing reports, an ongoing registry-based ELX/TEZ/IVA postauthorization safety study, and peer-reviewed literature suggests that depression symptoms and depression-related events reported in pwCF treated with ELX/TEZ/IVA are generally consistent with background epidemiology of these events in the CF population and do not suggest a causal relationship with ELX/TEZ/IVA treatment.

Decreases in Rhinology Care Utilization by People with Cystic Fibrosis on Highly Effective Modulator Therapy.

BACKGROUND: Many people with cystic fibrosis (PwCF) have chronic rhinosinusitis (CRS). CRS requires additional management beyond that of pulmonary disease and leads to increased utilization of healthcare resources. Elexacaftor/tezacaftor/ivacaftor (ETI) is a highly effective modulator therapy that has been shown to improve CRS in PwCF. However, the impact of ETI on rhinologic healthcare utilization is understudied. OBJECTIVE: To compare rates of rhinologic healthcare utilization and procedures among PwCF prior to and after initiating ETI therapy. METHODS: A single-center, cohort study investigating adult PwCF was performed in January 2023. Demographics, clinical characteristics, and data related to CF treatment were retrospectively abstracted. Characteristics of the cohort were compared over 2 periods: the 12-months prior to ETI initiation and the 12-months after ETI initiation. Post-ETI data were linearly extrapolated if a subject had not yet completed the full 12 months of ETI. Paired t-testing, Wilcoxon signed rank testing, and regression analysis were performed. RESULTS: Of 126 PwCF, 98 (77.8%) were on ETI therapy and 35 (27.7%) were both on ETI and concurrently followed by the rhinology service (ETI-ENT). Rhinology clinic visits (P = .007) and frequency of obtaining nasal cultures (P = .046) decreased for the ETI-ENT cohort after initiating ETI treatment. There were no significant changes in the number of endoscopic sinus surgeries (P = .452) performed. Beyond ETI use, regression analysis did not identify any factors associated with changes in utilization. CONCLUSION: Aspects of rhinology healthcare utilization by PwCF decreased after initiation of ETI therapy. Additional studies are needed to determine rhinologic healthcare requirements for PwCF who remain on ETI for the long-term and to evaluate larger cohorts of PwCF on ETI.

Chronic rhinosinusitis and olfaction after highly effective modulator therapy: The role of individual sinus inflammation.

KEY POINTS: Individual sinus opacification (ISO) is measurable via a convolutional neural network approach. ISO decreased through 2 years after highly effective modulator therapy was initiated. In adults with cystic fibrosis, ISO did not correlate with quality of life or olfaction.

Determining the minimal clinically important difference for the questionnaire of olfactory disorders in people with cystic fibrosis and factors associated with improvement after highly effective modulator therapy.

INTRODUCTION: Olfactory dysfunction (OD) is common among people with cystic fibrosis (PwCF). The Questionnaire of Olfactory Disorders (QOD) is a validated instrument that evaluates olfactory-specific quality-of-life. The QOD minimal clinically important difference (MCID) and factors associated with olfactory improvement after elexacaftor/tezacaftor/ivacaftor have not been determined for PwCF. METHODS: Prospective observational data were pooled from three studies that enrolled adult PwCF with chronic rhinosinusitis (CRS). QOD scores and disease characteristics were assessed. To evaluate internal consistency and calculate the QOD MCID, Cronbach's alpha and four distribution-based methods were employed. For participants who enrolled prior to elexacaftor/tezacaftor/ivacaftor, QOD scores were obtained at baseline and after elexacaftor/tezacaftor/ivacaftor initiation. Multivariable regression was used to identify factors associated with QOD improvement. RESULTS: Of 129 PwCF included, 65 had QOD scores before and 3-6 months after starting elexacaftor/tezacaftor/ivacaftor. Mean baseline QOD score was 6.5 ± 7.9. Mean Cronbach's alpha was ≥0.85. The MCID estimates were as follows: Cohen's effect size = 1.6, standard error of measurement = 2.5, ½ baseline standard deviation = 4.0, and minimal detectable change = 6.9. Mean MCID was 3.7. Of those with pre/post elexacaftor/tezacaftor/ivacaftor QOD scores, the mean change in QOD was -1.3 ± 5.4. After elexacaftor/tezacaftor/ivacaftor, QOD improvement surpassed the MCID in 22% of participants (14/65). Worse baseline QOD scores and nasal polyps were associated with improved QOD scores after elexacaftor/tezacaftor/ivacaftor (both p < 0.04). CONCLUSION: The QOD MCID in PwCF was estimated to be 3.7. Elexacaftor/tezacaftor/ivacaftor led to qualitative but not clinically meaningful improvements in QOD score for most PwCF; PwCF with worse baseline QOD scores and nasal polyps improved in a clinically significant manner.

Long-term safety and efficacy of elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis and at least one F508del allele: 144-week interim results from a 192-week open-label extension study.

BACKGROUND: In two pivotal phase 3 trials, up to 24 weeks of treatment with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) was efficacious and safe in patients with cystic fibrosis (CF) ≥12 years of age who have at least one F508del allele. The aim of this study is to assess long-term safety and efficacy of ELX/TEZ/IVA in these patients. METHODS: In this phase 3, open-label, single-arm extension study, participants with F508del-minimal function (from a 24-week parent study; n=399) or F508del-F508del (from a 4-week parent study; n=107) genotypes receive ELX/TEZ/IVA at the same dose (ELX 200 mg once daily, TEZ 100 mg once daily and IVA 150 mg every 12 h). The primary end-point is safety and tolerability. A prespecified interim analysis was conducted when the last participant reached the Week 144 visit. RESULTS: At the Week 144 interim analysis, mean duration of exposure to ELX/TEZ/IVA in the extension study was 151.1 weeks. Exposure-adjusted rates of adverse events (AEs) (586.6 events per 100 participant-years) and serious AEs (22.4 events per 100 participant-years) were lower than in the ELX/TEZ/IVA treatment group in the 24-week parent study (1096.0 and 36.9 events per 100 participant-years, respectively); most participants had AEs classified as mild (16.4% of participants) or moderate (60.3% of participants) in severity. 14 participants (2.8%) had AEs that led to treatment discontinuation. Following initiation of ELX/TEZ/IVA, participants had increases in forced expiratory volume in 1 s (FEV1) percentage predicted, Cystic Fibrosis Questionnaire-Revised respiratory domain score and body mass index, and had decreases in sweat chloride concentration and pulmonary exacerbation rates that were maintained over the interim analysis period. The mean annualised rate of change in FEV1 % pred was +0.07 (95% CI -0.12-0.26) percentage points among the participants. CONCLUSIONS: ELX/TEZ/IVA was generally safe and well tolerated, with a safety profile consistent with the 24-week parent study. Participants had sustained improvements in lung function, respiratory symptoms, CF transmembrane conductance regulator function, pulmonary exacerbation rates and nutritional status. These results support the favourable safety profile and durable, disease-modifying clinical benefits of ELX/TEZ/IVA.

A provider survey assessing fetal impact of CFTR modulator use in males with CF during assisted and unassisted reproduction and partner pregnancy.

BACKGROUND: Most males with cystic fibrosis (mwCF) are infertile but with CF transmembrane conductance regulator (CFTR) modulator-conferred benefits, more are utilizing assisted reproductive technologies (ART). Administration of normal human doses of modulators in animal reproductive models caused no genotoxicity; no human data exists. Potential health decline following modulator discontinuation makes the decision to withhold therapy during reproduction challenging. METHODS: From August-October 2021, international CF clinicians completed an anonymous questionnaire regarding mwCF who used modulators during reproduction. RESULTS: We received 42 surveys for mwCF with partner pregnancies. Forty of 42 mwCF utilized ART; 35 continued modulators during sperm retrieval and 40/42 during partner pregnancy. One of four males who discontinued modulators experienced clinical deterioration. First trimester miscarriages occurred in 11.9 % of partner pregnancies. No congenital anomalies were reported. CONCLUSIONS: Use of CFTR modulators during reproduction and partner pregnancy in mwCF did not result in a higher-than-expected miscarriage rate nor congenital anomalies.

Clinician perspectives and practices related to sexual and reproductive care provision for males with cystic fibrosis.

BACKGROUND: Males with cystic fibrosis (MwCF) have unique sexual and reproductive health (SRH) concerns. This study investigates multidisciplinary CF clinician perspectives related to SRH for MwCF in the current era of CF care. METHODS: We surveyed multidisciplinary clinicians exploring attitudes, practices, and preferences toward male CF SRH care. We compared responses across groups by population served (pediatric vs. adult vs. both pediatric and adult MwCF) using chi square/Fisher's exact tests. RESULTS: A total of 297 clinicians completed the survey (41 % pediatric, 36 % adult, 23 % both; 27 % physicians, 24 % social workers, 11 % nurses, 41 % other). Nearly all (98 %) believed the CF team had a role in SRH care with 75 % believing they should be primarily responsible. Pediatric clinicians were less likely to deem SRH topics important and less likely to report annual discussions compared to adult colleagues (all p<0.05). Pediatric clinicians reported less comfort in their SRH knowledge than adult colleagues (p<0.001) and in their ability to provide SRH care (p<0.05). Common barriers endorsed by respondents included lack of SRH knowledge (75 %) and presence of family/partners in exam room (64 %). A majority rated SRH screening tools (91 %), partnerships with SRH specialists (90 %), clinician training (83 %), and management algorithms (83 %) as potential facilitators. CONCLUSION: Multidisciplinary CF clinicians perceive SRH for MwCF as important but report suboptimal SRH discussions. Pediatric clinicians report significantly less comfort and skill in discussing and managing male SRH. Identified barriers and facilitators should be used to improve SRH care for MwCF.

Olfactory loss in people with cystic fibrosis: Community perceptions and impact.

BACKGROUND: Olfactory dysfunction (OD) is prevalent in people with cystic fibrosis (PwCF) and can negatively impact quality-of-life (QOL). This study evaluated perceptions of OD, investigated how OD impacts QOL, and assessed willingness to participate in OD research among the CF community. METHODS: A 21-question survey was distributed through the CF Foundation's Community Voice program in 2023. The survey included questions on olfaction and interest in research. The Brief Questionnaire of Olfactory Disorders (BQOD), a validated person-reported outcome measure to assess QOL, was included. RESULTS: Seventy-six responses were received. Overall, 91% (69/76) reported olfactory problems. Mean BQOD score was 5.0 (standard deviation=4.8), indicating olfactory QOL impairment was present. Ninety-five percent (72/76) reported research on OD is worthwhile and were willing to participate in research. CONCLUSION: Among PwCF, OD and olfactory-specific QOL impairments are prevalent. There is strong interest and willingness to participate in OD research among the CF community.

The modern landscape of fertility, pregnancy, and parenthood in people with cystic fibrosis.

PURPOSE OF REVIEW: With improved long-term survival and the expanding availability of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies that treat the underlying genetic defect in cystic fibrosis, more people are interested in parenthood. Cystic fibrosis care centers and people with cystic fibrosis need more information to guide decisions related to parenting. RECENT FINDINGS: Here we present currently available data on fertility, pregnancy, and parenthood in the modern era of cystic fibrosis care. Fertility may be improving in female individuals with cystic fibrosis with the use of CFTR modulator therapies, and there is an associated increase in annual pregnancies. Infertility in male individuals with cystic fibrosis remains approximately 97-98% and is unchanged with CFTR modulators in those already born with cystic fibrosis. As more female individuals with cystic fibrosis experience pregnancy, questions remain about the impact of pregnancy on their health and that of their child. Fortunately, there are multiple routes to becoming a parent; however, more work is needed to understand the impact of pregnancy and parenthood in the context of CF as some previous data suggests potential challenges to the health of parents with cystic fibrosis. SUMMARY: We encourage cystic fibrosis care teams to have knowledge and resources available to support the reproductive goals of all individuals with cystic fibrosis.

CFTR modulator therapy: transforming the landscape of clinical care in cystic fibrosis.

Following discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 1989 and subsequent elucidation of the varied CFTR protein abnormalities that result, a new era of cystic fibrosis management has emerged-one in which scientific principles translated from the bench to the bedside have enabled us to potentially treat the basic defect in the majority of children and adults with cystic fibrosis, with a resultant burgeoning adult cystic fibrosis population. However, the long-term effects of these therapies on the multiple manifestations of cystic fibrosis are still under investigation. Understanding the effects of modulators in populations excluded from clinical trials is also crucial. Furthermore, establishing appropriate disease measures to assess efficacy in the youngest potential trial participants and in those whose post-modulator lung function is in the typical range for people without chronic lung disease is essential for continued drug development. Finally, recognising that a health outcome gap has been created for some people and widened for others who are not eligible for, cannot tolerate, or do not have access to modulators is important.

Advancing the pipeline of cystic fibrosis clinical trials: a new roadmap with a global trial network perspective.

The growing use of modulator therapies aimed at restoring cystic fibrosis transmembrane conductance regulator (CFTR) protein function in people with cystic fibrosis has fundamentally altered clinical trial strategies needed to advance new therapeutics across an orphan disease population that is now divided by CFTR modulator eligibility. The development of a robust pipeline of nucleic acid-based therapies (NABTs)-initially directed towards the estimated 10% of the cystic fibrosis population who are genetically ineligible for, or intolerant of, CFTR modulators-is dependent on the optimisation of restricted trial participant resources across multiple development programmes, a challenge that will preclude the use of gold standard placebo-controlled trials. Advancement of a full pipeline of symptomatic therapies across the entire cystic fibrosis population will be challenged by smaller effect sizes and uncertainty regarding their clinical importance in a growing modulator-treated population with more mild and stable pulmonary disease. In this Series paper, we aim to lay the foundation for clinical trial strategy and community partnership that must deviate from established and familiar precedent to advance the future pipeline of cystic fibrosis therapeutics.